1. Field of the Invention
The present invention relates, generally, to specimen collection and more particularly, to a method and device for collecting and determining the presence of occult blood in fecal matter and a test kit containing such a device.
2. Description of Related Art
Over 100,000 persons per year in the United States are afflicted with cancer of the colon and rectum. When the number of colon/rectal cancers occurring each year is combined with the number of cancers occurring in other digestive organs, including the esophagus and stomach, such cancers of the digestive system account for more occurrences of cancer than any other single form of the disease. Contrary to many other forms of cancer, early diagnosis and treatment of digestive tract cancer does result in a cure rate of about 80% to 90%. If, however, the disease is not detected until the later stages, the cure rate drops significantly. Thus, early detection of the disease is important to successful treatment of digestive tract cancer.
Most, but not all, cancers of the digestive tract bleed to a certain extent. This blood is deposited on and in fecal matter excreted from the digestive system. The presence of blood in fecal matter is not normally detected, however, until gross bleeding, that is, blood visible to the naked eye, occurs. Gross bleeding, however, is symptomatic of advanced cancers.
Digestive tract cancers in the early stages, including pre-cancerous polyps, also tend to bleed, giving rise to occult (hidden) blood in the fecal matter. Other pathological conditions, such as Crohn's disease and diverticulitis, can also give rise to the presence of occult blood in the fecal matter.
It is known that because of the relatively high fat content of fecal matter, blood, when present, is not distributed uniformly throughout it. For this reason, obtaining multiple samples from different areas of each bowel movement is desirable; but even a single positive test from any part of the feces should be considered a positive result.
Accordingly, test equipment and test procedures have been developed for use by physicians in testing for the presence of occult blood in fecal matter. There are two popular types of fecal sampling devices, wipe-style devices and slide-style devices.
An example of a wipe-type device is described in Levine U.S. Pat. No. 4,367,750 and an example of a slide-type device is described in U.S. Pat. No. 3,996,006. In general, whereas the wipe-type device includes a disposable layer that is wiped across the patient's anus to collect a sample and is then discarded, the slide-type device is not brought in contact with the patient's anus.
One drawback of existing devices is that the positive indication is often difficult to observe due to too much specimen being applied to the paper. Thus, a need exists for an improved fecal sampling device, including one having improved readability.